CVE-2024-24791: Go Standard Library Net/http

High severity, CVSS 7.5. EPSS: 1.4% chance of exploitation in the next 30 days.

The net/http HTTP/1.1 client mishandled the case where a server responds to a request with an "Expect: 100-continue" header with a non-informational (200 or higher) status. This mishandling could leave a client connection in an invalid state, where the next request sent on the connection will fail. An attacker sending a request to a net/http/httputil.ReverseProxy proxy can exploit this mishandling to cause a denial of service by sending "Expect: 100-continue" requests which elicit a non-informational response from the backend. Each such request leaves the proxy with an invalid connection, and causes one subsequent request using that connection to fail.

Affected products

• Go Standard Library Net/http: before 1.21.12 (fixed in 1.21.12); from 1.22.0-0, before 1.22.5 (fixed in 1.22.5)
• Go Standard Library Net\/http: before 1.21.12 (fixed in 1.21.12); from 1.22.0-0, before 1.22.5 (fixed in 1.22.5)

Published 2024-07-02. Last modified 2026-06-17.